||Wright-Patterson AFB, OH 454337542
Electronic warfare (EW) receiver is a unique receiver that detects unknown radar signals in a real-time situation. EW wideband digital receiver contains a front analog subsystem and a back digital subsystem. Much effort has been done to improve the performance of the front subsystem. The digital subsystem usually includes time-frequency transfer and signal detection encoder. We are interested in the development to achieve an overall EW receiver performance. Several topics are under consideration:
(1) Dynamic range improvement in two-signal detection. Understanding and effective modeling of the nonlinear effects due to the analog components in the front subsystem is the first step. The efficient algorithm may then be developed to compensate the effect. The algorithm is preferable to be adaptive and in real-time.
(2) There are various filter bank designs to track wideband signals. Are there optimized filter design and encoder algorithm to effectively detect multiple signals simultaneously? Understanding the fundamental limitation such as the time and frequency resolutions, and the current specifications of the target signal is the first step. The ringing (rabbit ear) effect due to the pulse edges may impose performance limitation with filter bank design.
(3) Besides Continuous Wave (CW) and pulsed CW signals, we are also interested in automatic recognition of the modulation signals, Including Binary Phase Shift Key (BPSK) and chirp pulses commonly observed in radar signals.
(4) Multiple-channel receiver with a phase array is available in our laboratory. Research on digital beam forming techniques for the direction finding of the emitting source is in progress.
This research effort includes the model development, followed by numerical simulation to prove the feasibility of algorithm. Preferably, the development can be validated by hard/firmware implementation.
Electronic warfare receiver; Nonlinear effects; Direction finding; Automatic modulation recognition;